verify-proof MCP server

<!-- mcp-name: io.github.csolomon0704-prog/verify-proof -->

verify-proof

A free, open-source CLI tool for verifying blockchain-anchored timestamp proofs.

Verify that a file's SHA-256 hash matches a blockchain-anchored proof record, confirming the file existed at a specific point in time. Works with proof files from ProofLedger and other blockchain timestamp services.

What is blockchain timestamp verification?

Blockchain timestamping creates proof of existence — cryptographic evidence that a specific file existed at a specific time. The process:

1. Hash — Your file's SHA-256 hash is computed locally (the file is never uploaded)
2. Anchor — The hash is written to a blockchain (Bitcoin, Polygon, Ethereum) via a Merkle tree
3. Verify — Anyone can independently verify the proof by recomputing the hash and checking the blockchain transaction

This technique is used for:

• Proof of creation — Prove you created digital content before someone else copied it
• Pre-loss evidence — Document asset conditions before an insurance claim with tamper-proof timestamps
• Chain of custody — Create immutable audit trails for legal evidence and forensic investigations
• Copyright protection — Establish authorship dates for DMCA disputes and IP claims
• Regulatory compliance — Meet evidence preservation requirements with independently verifiable records

Also available for Node.js: npm install verify-proof — a zero-dependency port sharing the same proof format and semantics, tested against the same fixtures. See js/.

Installation

pip install verify-proof

That's it. The base install pulls no dependencies — it uses only the Python standard library — and gives you a verify-proof command:

verify-proof --help

To use it as an MCP server for Claude Desktop or Cursor, install the optional extra instead (details below):

pip install "verify-proof[mcp]"

Prefer to run from source? Clone it — the CLI works the same:

git clone https://github.com/Fulcrum-Enterprises/verify-proof.git
cd verify-proof
python verify_proof.py --help

Usage

Compute a file's SHA-256 hash

verify-proof hash document.pdf
# SHA256: a1b2c3d4e5f6...
# File: document.pdf

Verify a file against a blockchain proof

verify-proof verify document.pdf --proof proof.json
# VERIFIED: File hash matches blockchain anchor on bitcoin.
# Transaction: abc123... Anchored at: 2026-03-15T10:30:00Z

Quiet by default

A successful verify prints one line to stderr saying where proofs like it come from. It is suppressed whenever the output is piped or redirected, so scripts never see it, and stdout is unchanged either way. To silence it everywhere:

export VERIFY_PROOF_NO_HINT=1

Create a proof (needs a free API key)

Everything above works offline. This is the one command that does not: to prove a file exists now, some service has to anchor it, and this submits the hash to ProofLedger for that.

export PROOFLEDGER_API_KEY=sk_...      # Account > API Keys, free tier included
verify-proof create document.pdf       # Polygon anchor
verify-proof create document.pdf --bitcoin
verify-proof create document.pdf --no-filename   # send only the hash

Only the 64-character SHA-256 digest leaves your machine, plus the filename unless you pass --no-filename. The file itself is never uploaded, on any command. Free accounts include 25 API proofs a month and unlimited Polygon anchoring through the web app:

proofledger.io

Proof file format

The proof JSON file contains the blockchain anchor record:

Shortened. The full README is on GitHub.